1. Field of the Invention
The present invention relates to a magnetooptical recording and/or reproducing apparatus for recording information on a recording medium and reproducing the recorded information by projecting a focused optical beam on the medium and simultaneously applying a magnetic field. More particularly, this invention relates to a cartridge inserting/extracting apparatus for a portable magnetooptical disk player using a magnetooptical disk cartridge in which a magnetooptical disk is rotatably received.
2. Description of the Related Art
As is known well, a magnetooptical disk has recording layers in which desired information is recorded, and the recorded information is reproduced using a magnetooptical disk player which has an optical pickup for projecting a focused optical beam and a bias magnet for applying a magnetic field. These recording layers are composed of a magnetic material, for example, terbium-ferrum (TbFe) or terbium-ferrum-cobalt (TbFeCo). Such a magnetooptical disk is usually housed in a disk cartridge to be loaded on a disk drive together via a caddy. Recently, a magnetooptical disk cartridge called a "minidisk", into which a magnetooptical disk having a diameter of 64 mm is installed, was placed on the market by the Sony Corporation of Japan. Developments of the player for the minidisk have since progressed actively. There are two types of minidisks currently on the market: one is a recordable type shown in FIGS. 1A and 1B and the other is a reproduction-only type shown in FIGS. 2A and 2B.
Referring to FIGS. 1A and 1B, the recordable minidisk 1 has a cartridge cell 2 having two openings 3 and 4 formed on respective sides thereof, and a shutter 5 movably operated along a sliding groove 6 for opening and closing the openings 3 and 4 simultaneously. Both sides of the disk 9 in the cartridge cell 2 are exposed through the openings 3 and 4. The reproduction-only type of minidisk 1' has a cartridge cell 2' having an opening 3' on only one side thereof and a shutter 5' which moves along a sliding groove 6' for opening and closing the opening 3'. Thus, only one side of a disk 9' is exposed through the opening 3'.
Arrows 7 and 7' marked on the upper surface of the cartridge cells 2 and 2' of minidisks 1 and 1' show the direction for insertion into a player. Also, recording and reproducing detection grooves 8 and 8' each having a different size are formed on the bottom surface of each cartridge cells 2 and 2', for allowing detection of whether an inserted minidisk is a recordable type or a reproduction-only type. Two loading grooves 10 and 10' are provided on the left and right of the bottom of the disk cartridge cells 2 and 2' and a plurality of cartridge loading grooves 11 and 11' for facilitating loading of a disk cartridge into a deck are formed on the bottom of the cartridge cells 2 and 2'. Two fixing grooves 12 and 12' are provided on the sides of the disk cartridge (see FIGS. 1A and 2A).
A portable player (Sony model MZ-1) is available as a recording and reproducing apparatus for the minidisks. This player has a slot into which the minidisks can be inserted in a "slot-in" method, and includes a spindle motor for rotating the inserted minidisk, an optical pickup for projecting a focused optical beam onto one side of the disk, and a magnetic head for applying a magnetic field to the other side of the disk. The cartridge of the minidisk inserted into the slot is loaded into a deck, in the state in which the shutter is pushed aside and thereby the opening is opened, and at the same time the disk in the cartridge is loaded onto a rotating turntable by the spindle motor. If a reproducing mode is selected with respect to the rotating disk, then only the optical pickup operates in the state where the magnetic head is raised. If a recording mode is selected, then the magnetic head is lowered by a motor and thereby substantially contacts the other side of the disk and moves together with the optical pickup. Even when the recording mode is selected, if a reproduction-only minidisk is loaded, the magnetic head is not lowered.
Generally, it is desirable that a portable player be lightweight and compact and consume very little electrical power in order to operate as long as possible. However, since the inserting mechanism of the minidisk in the "slot-in" method and the mechanism for raising and lowering the magnetic head using a motor are complicated and require a large amount of space, it is difficult to make the player small and lightweight as a whole. Also, power consumption is excessive since the minidisk is inserted and/or extracted and the magnetic head is raised and/or lowered by separate electric driving means.
An attempt at solving these problems is disclosed in Korean Patent Application No. 93-9798. As shown in FIGS. 3 and 4, if the recordable type minidisk 1 is inserted into a cartridge holder 20, then a locking protrusion 55 of an extracting member 50 is hung on a locking pin 61 and a locking portion 95 of a slide locking member 90 is hung on a locking pin 94. Since the recordable type disk cartridge 1 pushes a protruding pin 85 and thereby a slide member 30 retreats and simultaneously a supporting stick 86 supporting a protrusion portion 45 of a head supporting member 32 retreats and the head supporting member 32 is lowered, a magnetic head 30 contacts the top of a disk 9. However the lowered magnetic head 30 may become damaged if a user pulls out the minidisk 1 to exchange it with another while the cartridge holder 20, in which the minidisk 1, is received is still open.